Compounds classified as corticosteroids, such as triamcinolone, can effectively treat some forms of neovascularization such as corneal neovasularization. In general, corticosteroids have been unsuccessful in treating neovscularization of the posterior segment. In many patients, these compounds cause undesirable side effects. These adverse affects include elevations in intraocular pressure and the formation of, or acceleration of, the development of cataracts. Elevations in intraocular pressure are of particular concern in patients who are already suffering from elevated intraocular pressure, such as glaucoma patients. Moreover, a risk exists that the use of corticosteroids in patients with normal intraocular pressure will cause elevations in pressure that result in damage to ocular tissue. Since therapy with corticosteroids is frequently long term, i.e., several days or more, a potential exists for significant damage to ocular tissue as a result of prolonged elevations in intraocular pressure attributable to that therapy.
One approach to solving the foregoing problems has been to search for specific compounds which are effective in treating neovascularization without elevating intraocular pressure. Another approach has been to administer corticosteroids in conjunction with another drug to "block" or reduce the IOP elevating effects of the corticosteroids or to treat IOP elevation separately with another drug. A further approach has been to intravitreally inject corticosteroids to treat ocular neovascularization.
There exists a need for an improved method for treating and/or preventing retinal diseases with corticosteroids.